Flexible bow construction

ABSTRACT

A boat hull including a flexible outer bow supported in forward spaced relation relative to a rigid inner bow structure with a cushion of air under pressure maintained between the rigid inner bow and the inner surfaces of the flexible outer bow. The hull includes generally flat forward bottom surfaces which join with the lower portions of the rigid inner bow structure and opposite side air plenum chambers to which large quantities of air under pressure is supplied. The forward portions of the side plenum chambers are communicated with opposite sides of the bow chamber defined between the inner bow and the flexible bow for inflating the latter and the lower transverse portions of the flexible bow are not sealingly secured to the corresponding portion of the rigid bow whereby air from the bow air chamber is discharged rearwardly beneath the forward bottom surfaces of the hull.

United States Patent [72] Inventor John Van Veldhuizen 31601 S.W. 197th Avenue, Homestead,

Fla. 33030 [21] Appl. No. 867,599 [22] Filed Oct. 20, 1969 [45] Patented Aug. 10, 1971 [54] FLEXIBLE BOW CONSTRUCTION 11 Claims, 5 Drawing Figs.

[52] 0.8. CI 114/67 A [51] Int. 1363b [/38 [50] FieldolSearch 114/219, 67, 67. A

[56] References Cited UNITED STATES PATENTS 2,776,637 1/1957 Chadwick 1 14/219 3,459,147 8/1969 lsmay 1 14/67 Primary Examiner-Andrew H. Farrell AtromeysClarance A. O'Brien and Harvey B. Jacobson ABSTRACT: A boat hull including a flexible outer bow supported in forward spaced relation relative to a rigid inner bow structure with a cushion of air under pressure maintained between the rigid inner bow and the inner surfaces of the flexible outer bow. The hull includes generally flat forward bottom surfaces which join with the lower portions of the rigid inner bow structure and opposite side air plenum chambers to which large quantities of air under pressure is supplied. The forward portions of the side plenum chambers are communicated with opposite sides of the bow chamber defined between the inner bow and the flexible bow for inflating the latter and the lower transverse portions of the flexible bow are not sealingly secured to the corresponding portion of the rigid bow whereby air from the bow air chamber is discharged rearwardly beneath the forward bottom surfaces of the hull.

PATENTED AUG10|971 3.598.077

sum 1 OF 2 Fig.5 4

John Van Ve/dhuizen INVENTOR.

BY wan/E PATENTED AUG 1 01971 John Van Ve/dhuizen IN VliN'l'OK.

M4052. MW

FLEXIBLE BOW CONSTRUCTION The flexible bow construction of the instant invention has been designed to provide a bow structure for a hull which will yield under impact with waves and choppy water and thus not subject the rigid portions of the bow of the associated boat hull to high stresses due to impact with waves. The bow con struction may be utilized on any type of boat hull but is par ticularly well adapted for use on a boat hull such as that disclosed in my copending U.S.application, Ser. No. 678,630, filed Oct. 27, 1967.

The boat hull disclosed in my copending application comprises an amphibious boat including means for establishing a supporting air cushion beneath the bottom surfaces of the boat and thus the boat may be termed a "ground effects vehicle" capable of moving over both land and water. In the amphibious boat large driven blowers are provided for supplying the requisite air under pressure to form the air cushion beneath the boat and a portion of the air under pressure developed is discharged rearwardly from the stern of the boat for propulsion while means is also provided for selectively discharging portions of the air under pressure forwardly and outwardly from opposite sides of the bow of the amphibious boat for stopping, reversing and maneuvering.

In addition to the flexible bow of the instant invention being practical for use on various types of boat hulls, it is particularly well adapted for use on an amphibious boat hull such as that disclosed in my above pending application and which includes an inclined transversely straight scow bow for maximum internal volume within the overall length and width dimensions of the amphibious boat. Further, inasmuch as the amphibious boat is an air cushion vehicle capable of relatively high speeds and the pay load thereof is detennined by the weight over and above the displacement of the amphibious boat which can be supported and still propelled by air from the power source provided, the general structure of the amphibious boat is of lightweight construction including the utilization of lightweight materials wherever possible in order to maintain the displacement of the amphibious boat at a minimum so as to afford maximum payload capacity. Of course, by utilizing a lightweight hull as an air cushion vehicle capable of travel over water atrelatively high speeds, the possibility is greater that impact of the hull with a chop or wave will cause a structural damage to the amphibious boat. Hence, a need exists for the provision of means whereby an amphibious air cushion boat may have its bow portion protected from harsh impact with waves and choppy water. It is therefore the main object of this invention to provide a flexible bow or false bow construction for utilization on an amphibious boat such as that disclosed in my above copending application and also on other boat hulls which will serve as an initial impact portion of the associated boat hull with waves and chops and thus at least initially breakup or smooth out waves or choppy water against which the associated boat hull is advanced.

It is a further object of this invention to provide a flexible bow construction of the type including an inflatable false bow for use in conjunction with an air cushion vehicle whereby the existing supply of air under pressure may be utilized to maintain the inflatable bow inflated.

Yet another object of this invention is to provide an inflata ble bow construction for an air cushion boat including .1 discharge port through which air within the inflatable bow may be readily forced therefrom but which is in direct communication with the forward portion of the air cushion area of the boat whereby the flexible bow may readily yield under impact with a large wave or chop by discharging the air within the flexible bow downwardly and rearwardly into the air cushion area of the boat, the air pressure in which air cushion area of the boat effectively resisting collapsing of the inflated bow construction upon impact with a medium size wave or chop and yet allowing substantial collapse of the inflated bow construction upon impact with a large wave or chop.

' construction in accordance with the preceding objects and which may readily be added to or incorporated in the manufacture of an amphibious boat such as that disclosed in my above copending application.

A final object of this invention to be specifically enumerated herein is to provide a flexible bow construction in accordance with the preceding objects which will conform to conventional forms of manufacture, be of simple construction and automatic in operation so as to provide a device that will be economically feasible, long lasting andrelatively troublefree in operation.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIG. I is a fragmentary perspective view of an amphibious boat having the flexible bow construction of the instant invention mounted thereon;

FIG. 2 is a further fragmentary perspective view of theforward portion of the embodiment of FIG. I as seen from below and with the flexible covering of the flexible bow construction removed in order to illustrate the structural details of the rigid supporting portion of the flexible bow construction and the manner in which air from the opposite side plenum chambers of the amphibious boat is ducted into the flexible bow construction;

FIG. 3 is an enlarged fragmentary longitudinal vertical section view taken substantially upon the plane indicated by the section line 33 of H0. 1;

FIG. 4 is a fragmentary transverse vertical sectional view taken substantially upon the plane indicated by the section line 4-4 of FIG. 3; and

FIG. 5 is a fragmentary horizontal sectional view taken substantially upon the plane indicated by section line 5-5 of FIG. 3

Referring now more specifically to the drawings the number 10 generally designates an amphibious boat such as that disclosed in my copending U.S. application Ser. No. 678,630. The boat 10 defines a hull including opposite sidewalls l2 and 14, a forward upper deck 18 and a forwardly and upwardly inclined "scow how" 20 extending between the sidewalls 12 and 14. In addition, the hull 10 includes a generally flat bottom 22 and the scow bow 20 extends rearwardly and downwardly from the forward marginal edge portion of the upper deck 18 to the forward marginal edge portion of the bottom 22.

The hull 10 further includes inner sidewalls l2 and i4 spaced inwardly of the sidewalls I2 and 14 and a pair of air plenum chambers 24 are defined between the walls 12 and i2 and the walls 14 and 14'. The lower marginal portions of the walls 12 and 12' as well as the walls 14 and 14 terminate downwardly in downwardly convergent portions 26 and 28 respectively, and each pair of convergent portions 26 and 28 defines a depending longitudinally extending side portion which depends downwardly from the bottom 22. These side portions define side boundaries for a downwardly opening recess defined beneath the bottom 22 and the portions 28 each have a plurality of longitudinally spaced openings 30 formed therein by which the downwardly opening recess defined between the side portions is communicated with the air plenum chambers 24.

Each side or sidewall I2 and 14 has an opening 30 formed therein slightly rearward of the bow 20 and a horizontally swingable control flap 32 is operatively associated with each opening 30 for opening and closing the latter in response to opening and closing of the control flap 32. Any suitable means (not shown) may be utilized to adjustably position the flaps 32 from a remote location and it will be noted that the flaps 32 are hingedly supported at the forward vertical edge portions and that their upper and lower marginal edge portions terminate below and above the upper and lower extremities of the associated air plenum chambers 24.

it is to be noted that the above description of the boat or hull may be considered substantially identical to the amphibious boat disclosed in my above copending US. application and that the boat 10 includes suitable driven blower means (not shown) for supplying large quantities of air under pressure to the air plenum chambers 24.

The flexible bow construction of the instant invention is referred to in general by the reference numeral 34 and includes a rigid framework 36 and a flexible covering 38. In addition to the provision of the framework 36 and the covering 38 and the mounting of these two structures on the boat [0, the only other modification is to the boat 10 in order to mount an operable flexible bow construction constructed in accordance with the present invention thereon is to provide the opposite side marginal portions of the scow bow with a plu rality of vertically spaced openings 40 formed therethrough whereby air under pressure from the forward ends of the air plenum chambers 34 may be bled into the flexible bow construction 34.

The framework 36 includes a pair of upper and lower transverse rigid members 42 and 44 and a pair of upstanding opposite side rigid members 46 and 48 interconnecting corresponding ends of the members 42 and 44. In addition, a generally semicircular rigid member 48 has its ends secured to the opposite ends ofthe upper transverse member 42 with the semicircular member 48 projecting forwardly from the transverse member 42. A plurality of different length upper horizontal brace members 50 are secured between the transverse member 42 and the semicircular member 48 with the brace members 50 generally paralleling each other and extending longitudinally of the boat 10. In addition, a plurality of different length inclined brace members 52 are provided and have their lower ends secured to portions of the lower transverse ember 44 spaced longitudinally therealong while their upper ends are secured to spaced portions of the semicircular member 48. The inclined brace members 52 are disposed in parallel upright planes extending longitudinally of the boat 10 and the various members numbered evenly from 42 through 52 may be of any suitable material such as stainless steel, aluminum or a marine alloy.

The cover 38 includes an upper horizontal panel 54 thereof of suitable flexible fluid impervious material which is secured over the members 48 and 50 and the forward marginal edge portion of the upper deck 18 as at 56. The cover 38 also in cludes a rearwardly and downwardly inclined panel 58 of similar material which is formed integrally with the panel 54 and which includesinclined corrugations 60 whose creaser portions 62 have supporting webs 64 formed integrally therewith and which extend rearwardly from the panel 58 am are secured to the members 52.

From FIGS. 2 and 3 of the drawings it may be seen that the transverse member 44 is spaced above the lower marginal edge of the scow how 20. However, it will also be noted that the lower marginal edge portion of the panel 58 extends downwardly below the bottom 22 and is secured to the forward undersurface portions of the opposite side depending portions defined by the downwardly divergent portions 26 and 28 as at 66. Only the opposite side corners of the lower marginal portion of the panel 58 are secured to the forward ends of the depending longitudinal portions and the opposite marginal edge portions of the panel 58 are secured to the forward marginal portions of the sidewalls l2 and 14 as at 68. Accordingly, the flexible bow construction 34 encloses an area defined between the inner surfaces of the panels 54 and 58 and the outer surface of the scow bow 20. However, this enclosed area is open to the forward end of the downwardly opening recess defined beneath the bottom 22, and communicated with the interior of the air plenum chambers 24 by way of the openings 40.

In operation, the boat 10 may be operated as an air cushion vehicle over the surface'of a body of water and moved forwardly at relatively high speeds with the impact of the false bow defined by the bow construction 34 cushioning the impact of the hull 10 with waves or choppy water. As the flexible panel 58 yields under impact with the waves, some portions of the air within the flexible bow construction 34 will backup through the openings 40 and other portions will be rearwardly beneath the bottom 22. However, the backup of air through the openings 40 is maintained at a minimum inasmuch as larger quantities of air from the bow construction 34 may be discharged rearwardly into the air cushion area beneath the bottom 22 of the hull 10 between the lower marginal portion of the panel 58 and the forward marginal edge portion of the bottom 22. lo this manner, pulsating air pressures within the air plenum chambers 24 due to the flexible bow construction 34 yielding under impact with waves or choppy water is maintained at a minimum and thus a more constant pressure of air within the air plenum chambers 24 is maintained for smoothness in propulsion and steerage by air bled from the air plenum chambers 24 at locations remote from the flexible bow construction 34.

From FIG. 2 of the drawings it will be noted that an ample supply of air may move forwardly through the air plenum chambers 24 and above and below the control flaps 32 for entrance into the flexible bow construction 34 through the openings 40. in addition, the flexible bow construction may be inflated and maintained fully operative with very little loss, if any, of the efficiency of the air cushion forming portions of the boat 10 even though air for inflating the flexible bow construction 34 is bled from the plenum chambers 24 which also serve to supply air to the air cushion formed beneath the boat 10. This is made possible by any air which is discharged from the inflatable bow construction 34 being discharged directly into the air cushion area beneath the bottom 22.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

What I claim as new is as follows:

1. A boat hull including a bow portion and a generally horizontal bottom extending rearwardly from the lower portion of said bow portion, a flexible and substantially air impervious panel supported from said hull in forwardly displaced position relative to said bow and including upper and lower transverse edges as well as opposite side edges, said upper and opposite side edges being sealingly secured to said hull and said lower transverse edge being disposed adjacent and including at least portions thereof free of sealed securement to said hull, and means operative to admit large quantities of air under pressure into the area between said panel and said how portion,

2. The combination of claim 1 wherein said bow portion and said panel are each forwardly and upwardly.

3. The combination of claim 2 wherein said panel includes flexible flange portions thereof which are generally parallel and project outwardly from the inner surface of said panel opposing said bow portion, said flange portions extending between the upper and lower marginal edge portions of said panel and being spaced apart transversely of said panel, said flange portions having their free edge portions stationarily anchored relative to said how portion.

4. The combination of claim 3 wherein said flange portions support at least the upper portions of said panel in forwardly peaked relation at least when the pressure of the air between said panel and said bow portion is greater than the pressure of air exteriorly of said panel.

5. The combination of claim 1 wherein said how portion includes forwardly and upwardly inclined forwardly facing surfaces, a frame supported from said bow including forwardly and upwardly inclined braces spaced transversely of said how portion and which diverge forwardly from said forwardly facing surfaces at their rear ends, the lower ends of said braces being supported closely adjacent said forwardly facing surfaces at a point spaced above the lower extremities of said forwardly facing bow surfaces, said panel including flexible flange portions thereof which are generally parallel and project outwardly from the inner surface of said panel opposing said bow portion, said flange portions extending between the upper and lower marginal edge portions of said panel and being spaced apart transversely of said panel, said flange portions having their free edge portions stationarily anchored relative to said braces.

6. The combination of claim 5 wherein the centrally disposed braces are moreforwardly inclined at their upper ends than the braces adjacent opposite the sides of said bow structure and the upper portions of said panel are supported from said braces in forwardly peaked relation.

7. The combination of claim 6 wherein said frame includes upper horizontal braces projecting forwardly from the upper marginal portion of said bow portion at points spaced transversely thereof and a curved transversely extending brace to which the forward ends of said horizontal braces and the upper ends of said inclined braces are secured.

8. The combination of claim 1 wherein said boat hull includes opposite side depending portions extending longitudinally thereof which project below said bottom, said means operative to admit large quantities of air under pressure into the area between said panel and said bow portion also including means operative to discharge large quantities of air under pressure into the area beneath said bottom bound by said depending portions.

9. The combination of claim 8 wherein the lower extremities of said side edges of said panel are secured to the forward ends of said depending portions.

10. A boat hull including a forward rigid inner bow structure having opposite side marginal portions and transversely extending upper and lower marginal portions, said hull also including generally horizontal forward bottom portion whose forward end portion is disposed adjacent said transversely extending lower bow portion, a flexible outer bow defining panel including upper and lower transverse edges as well as opposite side edges, said upper and opposite side edges being sealingly supported from said upper and opposite side marginal portions, respectively of said rigid bow structure, said hull including air plenum chamber means to which large quantities of air under pressure may be supplied, means communicating the interior of said chamber means with the space defined between the outer bow defining structure and the outer surfaces of said rigid inner bow structure, said lower transverse edge including at least portions thereof free of sealed securement to said hull and being disposed adjacent said forward end portion of said bottom portion of said hull.

11. A boat hull including a bow and a bottom defining a downwardly opening recess for containing a cushion of air, a flexible and substantially air impervious panel supported from said hull in forwardly displaced position relative to said bow and including upper and lower transverse edges as well as opposite side edges, said upper and opposite side edges being sealingly secured to said bow and said lower transverse edge being disposed adjacent the forward end of said recess and in cluding at least portions thereof free of sealed securement to said hull, said hull including chamber means into which large quantities of air under pressure may be pumped and passage means communicating said chamber means with said recess and the area defined between said bow and the opposing inner surfaces of said panel. 

1. A boat hull including a bow portion and a generally horizontal bottom extending rearwardly from the lower portion of said bow portion, a flexible and substantially air impervious panel supported from said hull in forwardly displaced position relative to said bow and including upper and lower transverse edges as well as opposite side edges, said upper and opposite side edges being sealingly secured to said hull and said lower transverse edge being disposed adjacent and including at least portions thereof free of sealed securement to said hull, and means operative to admit large quantities of air under pressure into the area between said panel and said bow portion.
 2. The combination of claim 1 wherein said bow portion and said panel are each forwardly and upwardly.
 3. The combination of claim 2 wherein said panel includes flexible flange portions thereof which are generally parallel and project outwardly from the inner surface of said panel opposing said bow portion, said flange portions extending between the upper and lower marginal edge portions of said panel and being spaced apart transversely of said panel, said flange portions having their free edge portions stationarily anchored relative to said bow portion.
 4. The combination of claim 3 wherein said flange portions support at least the upper portions of said panel in forwardly peaked relation at least when the pressure of the air between said panel and said bow portion is greater than the pressure of air exteriorly of said panel.
 5. The combination of claim 1 wherein said bow portion includes forwardly and upwardly inclined forwardly facing surfaces, a frame supported from said bow including forwardly and upwardly inclined braces spaced transversely of said bow portion and which diverge forwardly from said forwardly facing surfaces at their rear ends, the lower ends of said braces being supported closely adjacent said forwardly facing surfaces at a point spaced above the lower extremities of said forwardly facing bow surfaces, said panel including flexible flange portions thereof which are generally parallel and project outwardly from the inner surface of said panel opposing said bow portion, said flange portions extending between the upper and lower marginal edge portions of said panel and being spaced apart transversely of said panel, said flange portions having their free edge portions stationarily anchored relative to said braces.
 6. The combination of claim 5 wherein the centrally disposed braces are more forwardly inclined at their upper ends than the braces adjacent opposite the sides of said bow structure and the upper portions of said panel are supported from said braces in forwardly peaked relation.
 7. The combination of claim 6 wherein said frame includes upper horizontal braces projecting forwardly from the upper marginal portion of said bow portion at points spaced transversely thereof and a curved transversely extending brace to which the forward ends of said horizontal braces and the upper ends of said inclined braces are secured.
 8. The combination of claim 1 wherein said boat hull includes opposite side depending portions extending longitudinally thereof which project below said bottom, said means operative to admit large quantities of air under pressure into the area between said panel and said bow portion also including means operative to discharge large quantities of air under pressure into the area beneath said bottom bound by said depending portions.
 9. The combination of claim 8 wherein the lower extremities of said side edges of said panel are secured to the forward ends of said depending portions.
 10. A boat hull including a forward rigid inner bow structure having opposite side marginal portions and transversely extending upper and lower marginal portions, said hull also including generally horizontal forward bottom portion whose forward end portion is disposed adjacent said transversely extending lower bow portion, a flexible outer bow defining panel including upper and lower transverse edges as well as opposite side edges, said upper and opposite side edges being sealingly supported from said upper and opposite side marginal portions, respectively of said rigid bow structure, said hull including air plenum chamber means to which large quantities of air under pressure may be supplied, means communicating the interior of said chamber means with the space defined between the outer bow defining structure and the outer surfaces of said rigid inner bow structure, said lower transverse edge including at least portions thereof free of sealed securement to said hull and being disposed adjacent said forward end portion of said bottom portion of said hull.
 11. A boat hull including a bow and a bottom defining a downwardly opening recess for containing a cushion of air, a flexible and substantially air impervious panel supported from said hull in forwardly displaced position relative to said bow and including upper and lower transverse edges as well as opposite side edges, said upper and opposite side edges being sealingly secured to said bow and said lower transverse edge being disposed adjacent the forward end of said recess and including at least portions thereof free of sealed securement to said hull, said hull including chamber means into which large quantities of air under pressure may be pumped and passage means communicating said chamber means with said recess and the area defined between said bow and the opposing inner surfaces of said panel. 